Kansai Electric Power Co.'s Takahama No. 4 reactor was restarted Wednesday just over 14 months after it was forced to shut down, bringing to four the number of reactors currently operating in Japan.

"The No. 4 reactor was turned back on at 5 p.m. today. It's an important step, but it's not the end. We'll proceed with operations carefully, with an attitude of always having safety as the top priority," Kepco President Shigeki Iwane said in a statement following the restart.

Kepco officials reported no problems during Wednesday's final preparation to fire up the No. 4 reactor in Fukui Prefecture, which had been idle since a restart attempt was aborted in February last year when an alarm went off due to a problem with a generator.